Fig. 6.

Neuronal network maturation and synaptic development increase with respect to days in vitro. The mature neuronal and the putative synaptic marker densities increased in tandem slowly in the first 1.5 weeks in culture and rapidly in the second half of the second week. * indicates significant differences for both markers at 16 days in vitro compared to previous time points, p < 0.05. Insets show 3-D z-stack image projections of 11 days (~ 51 µm thick z-section) and 16 days (~ 55 µm thick z-section) old cultures, respectively. Dramatic changes are seen in the mature neuronal density (red MAP-2ab + ve), putative synaptic density (green Synapsin 1 + ve), and nuclear density (Blue Hoechst + ve) indicating significant culture development and remodeling. (Color figure online)